A Review of Non-Invasive Drug Delivery through Respiratory Routes

Abstract

With rapid and non-invasive characteristics, the respiratory route of administration has drawn significant attention compared with the limitations of conventional routes. Respiratory delivery can bypass the physiological barrier to achieve local and systemic disease treatment. A scientometric analysis and review were used to analyze how respiratory delivery can contribute to local and systemic therapy. The literature data obtained from the Web of Science Core Collection database showed an increasing worldwide tendency toward respiratory delivery from 1998 to 2020. Keywords analysis suggested that nasal and pulmonary drug delivery are the leading research topics in respiratory delivery. Based on the results of scientometric analysis, the research hotspots mainly included therapy for central nervous systems (CNS) disorders (Parkinson's disease, Alzheimer's disease, depression, glioblastoma, and epilepsy), tracheal and bronchial or lung diseases (chronic obstructive pulmonary disease, asthma, acute lung injury or respiratory distress syndrome, lung cancer, and idiopathic pulmonary fibrosis), and systemic diseases (diabetes and COVID-19). The study of advanced preparations contained nano drug delivery systems of the respiratory route, drug delivery barriers investigation (blood-brain barrier, BBB), and chitosan-based biomaterials for respiratory delivery. These results provided researchers with future research directions related to respiratory delivery.

Keywords: COVID-19; nanoparticles; nasal drug delivery; pulmonary drug delivery; scientometric analysis.

Figure 1

Flow chart of scientometric analysis of respiratory delivery.

Figure 2

The number of papers published from 1998 to 2020 in respiratory delivery.

Figure 3

Keywords map. (a) Top 20 keywords with the highest frequency. (b) Keywords co-occurrence network. Each node’s size indicates the keyword’s frequency. Links connecting two nodes represent a co-occurrence relationship between two keywords.

Figure 4

Application of respiratory delivery in disease therapy.

Figure 5

Different products for respiratory delivery [13,14,15,16,17,18].

Figure 6

Stimuli-sensitive preparations for respiratory delivery. Purple cluster: temperature-sensitive formulation, genipin/HP-β-CD inclusion complex; blue cluster: ionic-sensitive formulation, resveratrol nanosuspension-based in situ gels; orange cluster: pH-sensitive formulation, FePt-Lenalidomide nanoconjugates; green cluster: redox-sensitive formulation, bio-reducible hyperbranched poly (amido amine) [19,20,21,22].